They all look pretty good to me, and if you hadn't mentioned HDR i would not have guessed (which is how it should be, no clown sick HDR here)
The first is my favourite though, the leading lines of the path and the river work great
Not so keen on the last one, not sure the rooftop and chimney in the foreground add much to the image, other than that its just a photo of an empty car park really, but saying that the HDR treatment is still very nice, and certainly not overdone